General InformationThese toads are an easy to care for species from Northern Argentina, Paraguay, Southern Brazil, and Uruguay. What has been obtainable in the hobby mostly originated in Paraguay but there were also some importations from Argentina. Most, but not all, males are approximately 25 mm (1 inch) and females average about 30-35 mm (1.2-1.4 inches). Large females can reach 40 mm (1.6 inches) in some cases.

Family:

Bufonidae (True Toads)

Origin:

Argentina, Brazil, Paraquay, Uruguay

IUCN (Red List) Status:

Least Concern (LC)

CITES Status:

No Listing

Adult Snout-to-Vent Length:

Male: 25 mm (1 inch); Female: 30-35 mm (~1.3 inches)

Lifespan:

10 years or more

Captive Difficulty:

Intermediate

Breeding Difficulty:

Intermediate

Activity:

Strictly diurnal (active by day)

Temperature:

Day 21-27 °C (70-80 °F); Lower at night

Food:

Small insects such as crickets, moths, larger fruit flies, mealworms, waxworms, small captive cultured roaches, other arthropods, small earthworms

To my knowledge, there are two sub-species generally available in the hobby (circa 2001). The larger and more commonly available of the two has large yellow bars and swirls on the black background. The ventral side of its feet and thighs, in addition its “armpits”, are bright red with the remainder of the ventral surface being yellow and black, often with a few flecks of red on the yellow section of the belly. I believe this sub-species to be Melanophryniscus stelzneri fulvoguttatus. I have seen a number of examples of Melanophryniscus come in, in which the spots and bars are very nearly white, but these are usually mixed in with M. stelzneri fulvoguttatus, and as this is the only difference I have been able to discern, I believe them to be no more than a slightly different color variant of M. stelzneri fulvoguttatus. The other occasionally available sub-species I am aware of is smaller, and most specimens are 20-25 mm (0.8-1.0 inches). It has far less yellow and more black coloration than the previously mentioned sub-species. What yellow there is tends to be in small flecks or spots instead of large bars and swirls, and in most specimens the ventral is completely red and black with no yellow at all, or at most a few small flecks. I believe this sub-species to be M. stelzneri stelzneri.Captive CareTemperatures: These toads tolerate a broad temperature range. The ideal range seems to be 21-27 °C (70-80 ° F). Occasional temperatures into the low 30s °C (low 90s °F), or down to about 7 °C (mid-forties Fahrenheit) have not been harmful to my specimens, though the toads are not very active at these times. I maintain the humidity at 60-80% the majority of the time, as they are less active and hide when it gets much higher or lower.

I use both pea gravel and locally collected topsoil as substrate, but it can be leaves, ground coconut husk or anything that doesn’t make the humidity too high with the amount of ventilation you use. A shallow small to medium size water dish should be provided (I use an overturned Frisbee). Live or artificial plants, particularly Pothos (Devil’s Ivy, Epipremnum aureum), are recommended, as they improve the terrarium’s looks, and the toads seem to enjoy climbing up the plants. The toads are not very skilled climbers and often fall, but no harm results. Keep in mind when setting up the habitat that, although they are very adaptable, they are reported to be from a savanna-type area where they are said to have grasses and small shrubs rather than bromeliads and similar plants.

Feeding: These toads tend to be very enthusiastic eaters. Feeding adults is no problem as long as plenty of small food items are maintained. Keep in mind that they eat a lot of food for their size - more than a similar sized dart frog would eat. Pinhead crickets, fruit flies, termites, small harmless ant species, small roach nymphs, small silkworms, waxworms, and almost any other harmless insect of a similar size are acceptable as food items. They are such eager eaters that my adults will crawl into the water section of the tank, where they only occasionally go (although they swim fairly well), to eat the fruit flies that have fallen in and are crawling on the surface of the water.

I begin the breeding process by placing the female toads in a refrigerator at approximately 4-10 °C (40-50 °F) for approximately 4-5 days. This simulates “winter” and I have not found any more time to be necessary to stimulate the females to begin to develop eggs. It is not necessary to refrigerate the males at all, as I have found them to be simulated to clasp primarily by the “rain”, but refrigeration can be carried out if desired and no harm will result. After removing the females from the refrigerator, I place them in a small container at room temperature and feed them very heavily for approximately a week and a half. It is especially important to make certain that the females have all the food that they can possibly eat at this time or they may not develop eggs.
After around a week and a half I put all of the toads I wish to breed in a rain chamber. I prefer an ordinary household shower, as the water comes out more forcefully than most pump-type rain chambers. Where I live we have our own well, so nothing is added to the household water, but for most people this is not an option, and a safer method is to use a rain chamber with a pump recirculating tap water that has been treated with a proprietary dechlorinator like Amquel or Aquasafe.

I feel that my shower method this more closely simulates the heavy rainstorms that precede breeding in the wild. At any rate, it works for me. I just make certain that there is no soap or similar products on or in the shower that could harm them. I also see to it that the drain is covered with wire or plastic netting so the toads can’t go down the drain! After taking the necessary precautions, I leave them in the rain chamber for approximately half an hour. Then I raise the water level to 2.5-5 cm (1-2 inches) in depth. At this point I put a few things in for them to climb out on (sticks, plants, rocks, etc.), and I let the water run for the next hour. After about an hour and a half in the rain chamber I remove the toads to a well-planted (Pothos, sphagnum moss, etc.), gravel-based aquarium, 1/4 land and 3/4 water, with a water depth of 2.5-7.5 cm (1-3 inches). The males have often already embraced the females in amplexus when removed from the rain chamber. If not, they usually do so within a few hours of being placed in the aquarium. The eggs are usually laid by the following afternoon. If no eggs are laid by then, it becomes increasingly improbable that any will be. In that case, I return the toads to their normal setup. The males will release the females shortly.

Of Eggs, Tadpoles and Toadlets:At a water temperature of 26 °C (78 °F), the eggs hatch in about 48 hours, but this may vary by up to 12 hours each way. The optimal water temperature for eggs and tadpoles seems to be 23-26 °C (74-78 °F). I have raised tadpoles successfully at water temperatures from 20-28 °C (68-82 °F), but at both extremes I suffered somewhat higher mortality than in the optimal range.

The 4 mm (0.16 inch) tadpoles appear embryonic upon hatching and cling to the plants, sides of the tank, or sink to the bottom of the tank. After two days, the tadpoles begin to swim around more and they begin to feed on algae or algae-based fish food. The tadpoles should be given at least 13 sq. cm (2 sq. inches) of space each. After 7-10 days the tadpoles’ back limbs should become visible, and they will reach their maximum length of 14-18 mm (0.55-0.7 inches). In the next 5-7 days the front limbs will also emerge. Much care should be taken at this time because the froglets are very prone to drowning.

The method of rearing that I currently employ is a combination of stunted fruit flies and what I call the “compost heap method”. This entails setting up an enclosure (usually a 40 liter/10 US gallon tank for up to 60 or so 6-14 mm froglets) several months before it is needed. Use about 5 cm (2 inches) of earth in the bottom and plant a few small clumps of Pothos in one end of the tank. Then collect a handful or two of leaf litter and put it in the other end of the enclosure. Put some seed or feed corn on top of the leaf litter. Then collect earthworms, pillbugs, sowbugs, etc. and add them to the mix. Mist everything down and cover the tank so as to allow little ventilation. Don’t be afraid of mold if it grows - it doesn’t hurt a thing. Before you know it you will have a thriving colony of pillbugs, springtails, mites and various other tiny insects. When it is time for you to add the froglets it is advisable to increase the ventilation but do not permit the soil to dry out.

The froglets will grow quickly in such a setup, and with the addition of stunted D. melanogaster as needed, they easily double or even triple their size in the first month. By then they have developed some of their yellow and red coloration, and although the amount will continue to increase in the coming months, they already resemble miniature examples the adults. They will also become easier to feed as they are able to consume normal wingless D. melanogaster at this size.

They're not easy to sex but males should have raised areas on the "thumbs" of their front feet as well as being smaller and thinner than females.

Males of this strictly diurnal toad species do not have nuptial pads so looking at the "thumbs" is no help in M. stelzneri. Size can be a indicator of females since mature females are larger than males, but the only sure sign you have a male and not just a smaller female is calling.

I must have read, and re-read this post before purchasing my BBWT. It's a great article, nice pics, and really helped me create the best environment for my toad. This is my fourth amphibian and loving it! Congrats on the forum.